Disclosed herein is a method for automatically adjusting nip width based on a scanned nip print in an image production device, as well as corresponding apparatus and computer-readable medium.
The nip width is the measured arc distance created by the intersection of a soft fuser roll and a hard pressure roll in an image production device, such as a printer, copier, multi-function device, etc, which enables heat transfer and pressure needed to fuse prints. If the nip width is not set properly, toner is improperly melted and pressed (fused) against the paper resulting in image quality defects. In addition, improper nip setting can result in excessive wear of the fuser roll surface which results in image quality defects in the form of areas containing unacceptable differential gloss.
An accurate and consistent nip width increases fuser roll life by helping to minimize edge wear on the roll. It has been shown that uneven and excessive nip settings, inboard to outboard, result in accelerated edge wear. The nip width is supposed to be checked and adjusted with every fuser roll replacement. This measurement is not always done and combined with roll hardness varying significantly between batches, the roll nip widths are frequently set incorrectly. In addition, as the fuser roll ages the softness of the rubber changes resulting in less-than-optimum nip widths.
Conventional nip set up procedure requires the operator to manually load a blank piece of paper into the fuser nip to make an impression, dust the impressions with toner, and then measure the nip width with a small scale. Although this procedure is in the service documentation, it is not often performed with each fuser roll change. This manual process also leads to nip width variability. Although the variability may be within specification, it still results in significant delta gloss variability due to edge wear.